Hindered amine compounds are known to suppress the photodegradation of organic substances such as synthetic resins, and since the stabilization effect is different depending on the structure of the amine and the environment in which it is used, amines with active hydrogen atoms, amines without active hydrogen atoms and alkyloxyamines which are even more weakly basic than tertiary amines, have been considered for this purpose. The idea of introducing a triazine skeleton in order to enhance compatibility with the synthetic resin to be stabilized or its extraction resistance, has also been considered.
For example, prior art hindered amine compounds, when used with polyolefin resins, had low compatibility with the resin, and since they vaporized from the resin, they had the problem that their stabilization effect did not endure. Moreover, in applications where they came in contact with acid rain and agricultural chemicals, there was also the problem that they were extracted by the acid.
Hindered amine compounds having a carbonate structure have been proposed in Tokkai-Sho 62-273239 (claims and compounds No. 30, No. 31), Tokkai-Sho 63-75019 (claims and compounds I-19, I-20, I-21), for the purpose of stabilizing polyolefin resins or as a catalyst quencher in the manufacture of oxymethylene (co)polymers.
However, there is neither any disclosure nor suggestion of weakly basic hindered amine compounds having an alkyloxyamine structure.
As an example of a weakly basic hindered amine compound, a compound having such an alkyloxyamine structure is proposed in Tokko-Sho 49-40557 (claims), and weakly basic hindered amine compounds having various skeletons are proposed in Tokkai-Hei 1-113368 (claims), e.g., hindered amines having a carboxylate structure, amide structure, carbamate structure or acetal structure.
Since weakly basic hindered amine compounds show superior resistance to acid extraction, their practical use in polyolefin agricultural films has been proposed, e.g., in Tokkai-Hei 2001-139821 (claims).
However, there is neither any disclosure nor suggestion of weakly basic hindered amine compounds having a carbonate structure.
Many hindered amine compounds have been proposed in the prior art, but for example in the case of agricultural films, since light transmissivity (which depends on the stability of the resin in the film) has a major impact on the growth of crops, a hindered amine compound which had a better longer-term stabilization effect was desired.